Process of making india-rubber surgical instruments.



No. 721,768. PATENTED MAR. 3, 1903.

1 B. G. WORK.

PROCESS OF MAKING INDIA RUBBER SURGICAL INSTRUMENTS/ APPLICATION FILED-APR. 10, 1902.

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UNITED STATES PATENT OFFICE.

BERTRAM G. WORK, OF AKRON, OHIO, ASSIGNOR TO THE B. F. GOODRIOH COMPANY,OF AKRON, OHIO, A CORPORATION OF OHIO.

PROCESS OF MAKING INDIA-RUBBER SURGICAL INSTRUMENTS.

SEEGIFIOATION forming part of Letters Patent No. 721,768, dated March 3,1903. Application filed April l0, 1902. Serial No. 102.261. (Nspecimens.)

To aZZ whom it may concern.-

Be it known that I, BERTRAM G. WORK, a citizen of the United States, anda resident of the city of Akron, county of Summit, and State of Ohio,have invented certain new and useful Improvements in Processes of MakingIndia-Rubber Surgical Instruments, of which the following is aspecification.

India-rubber surgical instruments, such as objectionable. In themanufacture of these instruments, particularly catheters, it has beenthe practice to close such pocket. The methods of closing heretoforeemployed have resulted in the production of an instrument having itsclosed end solid. As compared with the hollow end this solid end is hardand unyielding. In the manufacture of catheters of rubber the end beyondthe eye is made solid with rubber of the same quality of which the bodyof the-instrument is made-that is, of rubber mixed with such ingredientsas may be necessary to render it suitable for vulcanization. Thevulcanization of the instrument is necessary, as non-vulcanized rubberbecomes hard at 32 Fahrenheit and soft and sticky at over 82 Fahrenheit.The mixture of such ingredients as are necessary for vulcanizationdecreases the elasticity of the rubber and increases its hardness, andthe process of vulcanization still further increases theincompressibility and hardness of the rubber. While the rubber catheterafter vulcanization is elastic, yet instruments thus made lack softnessand flexibility of the tip or rounded end'that is, the solid end beyondthe eye is comparatively hard. The

As this pocket is difficnlt to cleanse thoroughly, it is used to aconsiderable extent in catheterization, though the use of the hollow-endcatheter is recognized in the medical profession as a source of danger,it being virtuallyimpossible to cleanse the hollow end thoroughlywithout injury or destroying the instrument in that putrifyingsubstances may be introduced into the bladder, producing suppurativecystitis.

To retain the advantages of flexibility and softness of the hollow endand at the same time to avoid its concomitant dangers of infection, Ihave devised an improved method of filling the hollow end, whichconsists in closing the end prior to the vulcanization of the instrumentwith pure rubber, gum, or similar substance which is extremely soft andelastic and is unafi'ected by vulcanization and which in turn may becovered with or inclosed in rubber similar to that composing theremainder of the tubethat is, rubber suitable for vulcanization. so madehas a solid end; but the point so formed is readily flexed andcompressed and is so soft and supple as to cause a minimum of pain tothe patient, as it readily passes an obstruction and by reason of itselasticity again resumes its shape.

The drawings accompanying this specification illustrate myimprovement asapplied to one form of surgical instrument to which it is especiallyadaptedtha t is,to catheters-like reference letters indicatingcorresponding parts.

Figure 1 shows a flexible catheter. Fig. 2 shows the rounded end of acatheter in section at right angles to the plane of the eye, enlarged.Fig. 3 shows an olive-catheter in section, similarly enlarged.

A is the rounded end; B, the open end; 0, the tubular body; D, the eye;E, the filling, of pure rubber or similar material.

F is the catheter-walls, extended to unite with the back of the tubeproper and forming the sloping dam from the lower end of the eye upwardto the back of the tube inclosing the filling in theend A;

In practicing my invention I form the instrument in the desired shapefrom soft rubber with whichhas been mixed the necessary ingredients torender it vulcan'izable by The instrument any of the usual methods, asby molding. I then fill the pocket at the closed end up to the eye withpure gum. I prefer to coat this filling with soft rubber, such as thatof which the body of the tube is formed, in order to protect it fromforeign contact. The instrument so formed is then vulcanized. If theinstrument to be made is a probe, I fill the tube first formed withrubber-gum throughout its length, preferably closing the ends with thevulcanizable rubber of the tube, and then vulcanize the instrument. Theprocess of vulcanization does not affect the quality of elasticity orthe degree of softness of the crude gum forming the kernel or core ofthis instrument, merely serving to unite the inclosing sheath andtheinclosed kernel or core, so that they become integral.

The principle of my invention is applicable to all surgical instrumentsin which a soft resilient end is desirable in preference to a rigid end,as in throat or stomach tubes probes,

bougies, pessaries, and drainage-tubes; also to those surgicalinstruments in which an elastic and compressible body is desired.

Having thus described my invention, what I claim is- 1. In themanufacture of flexible surgical instruments of rubber, the process offorming a body of vulcanizable rubber, of including therein a core ofnon-vulcanizable rubber and of vulcanizing the instrument so formedsubstantially as described.

2. In the manufacture of elastic catheters, the method of forming theend beyond the eye solid, consisting in filling the hollow below the eyewith pure rubber, inclosing this filling with a vuloanizable coating andvulcanizing the catheter so formed substantially as described.

BERTRAM G. WORK.

Witnesses:

JOSEPH W. KELLEY, HARRY A. BAUMAN.

